A post-2014 troop level of that size has been recommended by Gen John Allen, the commander of US and NATO forces in Afghanistan, American media reports said quoting top US officials.

Under the emerging plan, NATO forces in parallel effort would advice Afghan forces at major regional military and police headquarters, but most likely with a minimal battlefield role.

NewYork Times said the planning for a post-2014 mission has emerged as an early test for President Obama in his new term as he tries to flesh out the strategy for transferring the responsibility for security to the Afghans. But it is not the only challenge: After the White House decides what sort of military presence to propose to the Afghan government for after 2014, it must turn to the question of how quickly to reduce its troop force before then.

As one of his last acts as senior American commander in Afghanistan, Gen John R Allen is expected to submit a formal recommendation for how quickly to begin withdrawing the United States' 66,000 troops. Two American officials who are involved in Afghan issues said that General Allen wants to keep a significant military capability through the fighting season ending in fall 2013, which could translate to a force of more than 60,000 troops until the end of that period.

Afghan forces are to assume the lead role for the war next year, and a military officer said that such a troop level would enable the United States to better support them, maintain the initiative and control critical terrain.